Fabian Castillo - FC Dallas - 24 Under 24

Even for the best and brightest young prospects, major success is no sure thing. 

The past winners of MLSsoccer.com's "24 Under 24" presented by EA SPORTS have seen their careers take a range of twists and turns since taking top honors in this poll. Here's a quick rundown of where they are now.

2010: Fredy Montero, Seattle Sounders FC

Montero has been all over the world since taking top honors in the inaugural 24 Under 24 rankings -- including a couple of loan spells while he was still under contract in Seattle.

The Sounders loaned him to Colombian side Millionarios in January 2013, then to Sporting Clube de Portugal in June of that year. The loan became a full-on transfer in January 2014, and Montero scored 27 league goals for the Lisbon side before transferring to Chinese Super League club Tianjin Teda this past February. 

Montero has made 22 appearances for the Tianjin Tigers, leading the club with seven goals and sharing the assists lead with three. 

2011: Brek Shea, FC Dallas

Shea broke out with a career-high 11 goals in 2011, was hampered by injury the following year, then moved to Premiership side Stoke City in January 2013. He failed to catch on there, making just three appearances for the Potters (in large part due to complications from offseason foot surgery in late 2012), and spent time on loan to Championship clubs Barnsley and Birmingham City.

The highest point of his England years came in 2013 -- but for country and not club, when Shea scored the winning goal against Panama in the final of the 2013 CONCACAF Gold Cup.

Shea returned to MLS in 2015 with Orlando City SC, and has three goals (all this year) and six assists in 44 league appearances with the Lions.

2012: Darren Mattocks, Vancouver Whitecaps FC

Mattocks took top honors in a solid rookie season, when he led Vancouver with seven goals (still his career high) in league play and also scored the Whitcaps' first playoff goal. He recorded career highs with 30 appearances and 20 starts in 2014, but started just nine of 22 appearances last year and was traded to the Portland Timbers this past March.

He has made 15 appearances and eight starts since joining the Timbers, with one goal and one assist.

Mattocks also has seen significant time with Jamaica's national team, scoring 12 goals in 31 appearances for the Reggae Boyz and helping them reach their first Gold Cup final in 2015 with two goals in the knockout rounds.

2013: Darlington Nagbe, Portland Timbers

Nagbe has been with the Timbers since breaking into the league in 2011 out of Akron, where he (like Mattocks) played for current Portland manager Caleb Porter. He took top honors with a nine-goal season in 2013, when he appeared in all 34 of the Timbers' MLS matches and all four of their playoff appearances.

He has been a model of dependability as a professional, missing just 17 regular-season matches over the course of his career (seven this year, due to a combination of injury and international duty) and appearing in all 10 postseason matches for the 2015 MLS Cup champions.

Nagbe became a U.S. citizen in 2015 and has made 10 appearances, scoring one goal, for his adopted country.

2014: DeAndre Yedlin, Seattle Sounders FC

Yedlin burst onto the big stage in 2014, helping the Sounders to a Supporters Shield/Lamar Hunt U.S. Open Cup double and appearing as a substitute in three matches for the United States at the FIFA World Cup in Brazil. He signed with England's Tottenham Hotspur in August, but remained in Seattle for the remainder of the season before going overseas in January 2015.

Yedlin played in only one Premier League match for Spurs, spending the 2015-16 season on loan to Sunderland and helping the Black Cats avoid relegation to the Championship. This summer, Yedlin transferred to Championship side Newcastle United.

His first goal in England came on Saturday, in a 2-0 victory over Derby County.

2015: Fabian Castillo, FC Dallas

If you don't know where Fabian Castillo is now, you didn't follow the summer transfer window very closely.

The Colombian striker's on-again, off-again move to Turkish side Trabzonspor (finally completed as a loan with an option to buy) was completed in early August, after he scored five goals in 22 league matches and one more in US Open Cup play for the Supporters Shield leaders and Open Cup finalists.

Castillo has appeared in three matches for Trabzonspor (whose fans were so thrilled by his arrival that they carried him out of the airport on their shoulders), but has yet to score.